Aims: Assessment of complications following implantation of transvenous ventricular electrodes to pace the left ventricle.
Methods and results: Twenty-eight patients with severe cardiac failure and left bundle branch block were prospectively followed for adverse effects of implantation of a left ventricular transvenous pacing system. Immediate follow-up was associated with loss of left ventricular pacing in nine patients (32%). This was due to lead dislodgement in four cases (corrected by re-operation in three of these cases), and due to increased threshold in five cases (corrected by programming a higher pacing amplitude in all five cases, but with intermittent diaphragmatic contraction in one case). After 1 month, one patient died, one patient with severe coronary heart disease suffered a myocardial infarction, and left ventricular pacing was lost in two patients. Pericardial effusion, new significant ventricular arrhythmias or other adverse effects were not observed. After a mean follow-up of 16 +/- 9.2 months, pacing leads remained stable and no late complications related to the transvenous left ventricular epicardial pacing were observed.
Conclusion: Placement of a permanent lead in a tributary of the coronary sinus is feasible without serious adverse effects during the first month. The only frequent adverse event was lead dislodgement; a finding which emphasizes the need for development of specially designed leads for this application.